The effect of regular salbutamol on lung function and bronchial hyperresponsiveness in normal subjects and nonasthmatic atopic subjects with allergic rhinitis.

Abstract

BACKGROUND: The effects of regular inhaled beta-agonist treatment on lung function remain a controversial issue. In an earlier study, the administration of regular inhaled salbutamol resulted in negative changes in FEV1 not only in asthmatics, but also in nonasthmatic atopic subjects. OBJECTIVE: The aim of this study was to confirm these findings and also to examine whether regular inhaled salbutamol would increase bronchial hyperresponsiveness in atopic or normal individuals. DESIGN: The study was a randomized, double-blind, placebo-controlled, crossover investigation. PARTICIPANTS: There were two groups: 10 normal healthy subjects (group A) and nine nonasthmatic atopic subjects (group B). INTERVENTIONS: Subjects received inhaled salbutamol or identical placebo for periods of 6 weeks, the dose being increased in stepwise fashion at 2-week intervals. MEASUREMENTS: Changes in lung function were assessed by measuring spirometric values, airways conductance, and changes in complete and partial expiratory flow volume curves. Changes in these parameters following a methacholine challenge were used to assess bronchial hyperresponsiveness. RESULTS: No statistically significant differences in lung function or bronchial hyperresponsiveness were noted to occur as the result of treatment in either group. CONCLUSION: Our results do not support the view that regular inhaled salbutamol in normal or atopic subjects without asthma causes adverse changes in the airways.